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-3 - <br />subsoils. Depths at which the samples were taken and the penetration resistance values are <br />shown on the Logs of Exploratory Borings, Figure 2. The samples were returned to our <br />laboratory for review by the project engineer and testing. <br />SUBSURFACE CONDITIONS <br />Graphic logs of the subsurface conditions encountered at the site are shown on Figure 2. The <br />subsoils consist of about M feet of topsoil (silty clay with organics) overlying stiff/medium <br />dense, silty sandy clay with small shale fragments down to the maximum depth explored, 36 feet. <br />The clay soils were stratified with higher shale content soils below about 10 to 15 feet. <br />Laboratory testing performed on samples obtained from the borings included natural moisture <br />content and density, Atterberg limits, gradation analyses and unconfined compressive strength. <br />The unconfined compressive strength testing performed on relatively undisturbed drive samples <br />of the deeper moist clay soils showed a stiff consistency. Atterberg limits testing indicates the <br />clay soils have low plasticity. Results of swell -consolidation testing performed on the lower <br />moisture content soils, presented on Figures 3 and 4, showed low to moderate compressibility <br />under conditions of loading and wetting. Results of gradation analyses testing performed on <br />small diameter drive samples of the silty sandy clay and clayey sand soils are shown on Figures <br />5 through 7. The laboratory testing is summarized in Table 1. <br />Free water was encountered in the borings at depth of about 14 to 25 feet at the time of drilling <br />and when checked 1 and 19 days later. The upper soils within about 10 to 15 feet of existing <br />ground surface were slightly moist increasing to moist and very moist with depth. <br />ENGINEERING ANALYSIS <br />Development of the site as generally planned should be feasible based on geotechnical <br />considerations. The groundwater conditions at the site will create potential problems during <br />construction unless the bottom of the pond is kept above the groundwater level. Placing a liner <br />near the groundwater level will require that the pond area be dewatered. The high moisture soils <br />will likely make excavation difficult due to potential soft subgrade conditions. The groundwater <br />level should not adversely impact the operation of the pond provided drawdown level of the <br />pond is kept above the high groundwater level. Potential impacts of the groundwater conditions <br />n-r�nulvuw Project No. 18-7-599 <br />